I've been thinking about this a lot lately. There are a lot of materials out there about "agencies" becoming trauma informed, but I find the materials more about organization, policies, procedures, décor - etc. But the TRUTH if the matter is that it's not an organization that becomes trauma informed, it is the staff. It's people. It's mindset and resultant behavior in acting toward others. What I HAVEN'T seen is any materials on that basic idea.
Agencies don't support people. People support people. Help is one on one - from the waiting room staff, to the therapist in the office - to the case worker in the field. Interaction is one on one. Sure - environment is important (a nice non-threatening waiting room, warm colors, etc.) but the bottom line is always people.
An agency can have all kinds of TIC activity going on, but if ALL of their staff are not aware of their mindset and resultant behavior towards the folks they support - all the best policies and procedures don't mean a thing.
So - that being said, I developed a flyer and hung it up in different places for my staff to look at and consider. We discuss the ideas behind it in supervision. All it is, is a series of clarifying questions about individual staff behavior based on the six underlying principles of what it is to practice Trauma Informed Care. (Kind of a Socratic Method approach to figuring out one's own behavior and attitude to fit in an overarching paradigm.)
I don't have any resources to point you toward - but I think these ideas will point you in a direction that will work for you and the folks you work with.